The prior art systems and methods of antifouling address themselves either to defouling an already fouled hull bottom, or to attacking only a portion of the marine fouling community. Apparently it was thought that some marine organisms are detachable from a ship hull because they are killed by fresh water, but it is known that some, in particular barnacles, have such a tenacious cement or adhesive action, that they are impossible to detach even though they can be killed. Also some algae, and grasses will grow in fresh water but not in the absence of light as is well known. The prior art appears to ignore the exclusion of light as a means to inhibit marine growth.
The use of antifouling coatings on ship bottoms is well known. These toxic coatings leach out a poison to kill growths before they form, but have a limited life of perhaps 1 to 2 years. Recently, the service life of these coatings has been extended to perhaps 5 years by using exotic and highly toxic materials, but both fouling and coatings must be mechanically removed and the hull then repainted by taking the ship out of service in a dry dock. In addition, toxic materials leached into the waters, or spread on the shore as dust during the abrasize blasting for removing the antifouling paints, contribute significantly to the pollution of the environment. Also any fouling of a ship bottom by the marine fouling community decreases the ship's speed capability and increases the fuel used for propulsion because of the rough bottom that is formed.